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-rw-r--r--arch/riscv/mm/init.c1566
1 files changed, 1566 insertions, 0 deletions
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
new file mode 100644
index 0000000000..0798bd861d
--- /dev/null
+++ b/arch/riscv/mm/init.c
@@ -0,0 +1,1566 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ * Copyright (C) 2020 FORTH-ICS/CARV
+ * Nick Kossifidis <mick@ics.forth.gr>
+ */
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/memblock.h>
+#include <linux/initrd.h>
+#include <linux/swap.h>
+#include <linux/swiotlb.h>
+#include <linux/sizes.h>
+#include <linux/of_fdt.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/libfdt.h>
+#include <linux/set_memory.h>
+#include <linux/dma-map-ops.h>
+#include <linux/crash_dump.h>
+#include <linux/hugetlb.h>
+#ifdef CONFIG_RELOCATABLE
+#include <linux/elf.h>
+#endif
+#include <linux/kfence.h>
+
+#include <asm/fixmap.h>
+#include <asm/io.h>
+#include <asm/numa.h>
+#include <asm/pgtable.h>
+#include <asm/ptdump.h>
+#include <asm/sections.h>
+#include <asm/soc.h>
+#include <asm/tlbflush.h>
+
+#include "../kernel/head.h"
+
+struct kernel_mapping kernel_map __ro_after_init;
+EXPORT_SYMBOL(kernel_map);
+#ifdef CONFIG_XIP_KERNEL
+#define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map))
+#endif
+
+#ifdef CONFIG_64BIT
+u64 satp_mode __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_57 : SATP_MODE_39;
+#else
+u64 satp_mode __ro_after_init = SATP_MODE_32;
+#endif
+EXPORT_SYMBOL(satp_mode);
+
+bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
+bool pgtable_l5_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
+EXPORT_SYMBOL(pgtable_l4_enabled);
+EXPORT_SYMBOL(pgtable_l5_enabled);
+
+phys_addr_t phys_ram_base __ro_after_init;
+EXPORT_SYMBOL(phys_ram_base);
+
+unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
+ __page_aligned_bss;
+EXPORT_SYMBOL(empty_zero_page);
+
+extern char _start[];
+void *_dtb_early_va __initdata;
+uintptr_t _dtb_early_pa __initdata;
+
+static phys_addr_t dma32_phys_limit __initdata;
+
+static void __init zone_sizes_init(void)
+{
+ unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
+
+#ifdef CONFIG_ZONE_DMA32
+ max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
+#endif
+ max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
+
+ free_area_init(max_zone_pfns);
+}
+
+#if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
+
+#define LOG2_SZ_1K ilog2(SZ_1K)
+#define LOG2_SZ_1M ilog2(SZ_1M)
+#define LOG2_SZ_1G ilog2(SZ_1G)
+#define LOG2_SZ_1T ilog2(SZ_1T)
+
+static inline void print_mlk(char *name, unsigned long b, unsigned long t)
+{
+ pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t,
+ (((t) - (b)) >> LOG2_SZ_1K));
+}
+
+static inline void print_mlm(char *name, unsigned long b, unsigned long t)
+{
+ pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t,
+ (((t) - (b)) >> LOG2_SZ_1M));
+}
+
+static inline void print_mlg(char *name, unsigned long b, unsigned long t)
+{
+ pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld GB)\n", name, b, t,
+ (((t) - (b)) >> LOG2_SZ_1G));
+}
+
+#ifdef CONFIG_64BIT
+static inline void print_mlt(char *name, unsigned long b, unsigned long t)
+{
+ pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld TB)\n", name, b, t,
+ (((t) - (b)) >> LOG2_SZ_1T));
+}
+#else
+#define print_mlt(n, b, t) do {} while (0)
+#endif
+
+static inline void print_ml(char *name, unsigned long b, unsigned long t)
+{
+ unsigned long diff = t - b;
+
+ if (IS_ENABLED(CONFIG_64BIT) && (diff >> LOG2_SZ_1T) >= 10)
+ print_mlt(name, b, t);
+ else if ((diff >> LOG2_SZ_1G) >= 10)
+ print_mlg(name, b, t);
+ else if ((diff >> LOG2_SZ_1M) >= 10)
+ print_mlm(name, b, t);
+ else
+ print_mlk(name, b, t);
+}
+
+static void __init print_vm_layout(void)
+{
+ pr_notice("Virtual kernel memory layout:\n");
+ print_ml("fixmap", (unsigned long)FIXADDR_START,
+ (unsigned long)FIXADDR_TOP);
+ print_ml("pci io", (unsigned long)PCI_IO_START,
+ (unsigned long)PCI_IO_END);
+ print_ml("vmemmap", (unsigned long)VMEMMAP_START,
+ (unsigned long)VMEMMAP_END);
+ print_ml("vmalloc", (unsigned long)VMALLOC_START,
+ (unsigned long)VMALLOC_END);
+#ifdef CONFIG_64BIT
+ print_ml("modules", (unsigned long)MODULES_VADDR,
+ (unsigned long)MODULES_END);
+#endif
+ print_ml("lowmem", (unsigned long)PAGE_OFFSET,
+ (unsigned long)high_memory);
+ if (IS_ENABLED(CONFIG_64BIT)) {
+#ifdef CONFIG_KASAN
+ print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END);
+#endif
+
+ print_ml("kernel", (unsigned long)kernel_map.virt_addr,
+ (unsigned long)ADDRESS_SPACE_END);
+ }
+}
+#else
+static void print_vm_layout(void) { }
+#endif /* CONFIG_DEBUG_VM */
+
+void __init mem_init(void)
+{
+#ifdef CONFIG_FLATMEM
+ BUG_ON(!mem_map);
+#endif /* CONFIG_FLATMEM */
+
+ swiotlb_init(max_pfn > PFN_DOWN(dma32_phys_limit), SWIOTLB_VERBOSE);
+ memblock_free_all();
+
+ print_vm_layout();
+}
+
+/* Limit the memory size via mem. */
+static phys_addr_t memory_limit;
+
+static int __init early_mem(char *p)
+{
+ u64 size;
+
+ if (!p)
+ return 1;
+
+ size = memparse(p, &p) & PAGE_MASK;
+ memory_limit = min_t(u64, size, memory_limit);
+
+ pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20);
+
+ return 0;
+}
+early_param("mem", early_mem);
+
+static void __init setup_bootmem(void)
+{
+ phys_addr_t vmlinux_end = __pa_symbol(&_end);
+ phys_addr_t max_mapped_addr;
+ phys_addr_t phys_ram_end, vmlinux_start;
+
+ if (IS_ENABLED(CONFIG_XIP_KERNEL))
+ vmlinux_start = __pa_symbol(&_sdata);
+ else
+ vmlinux_start = __pa_symbol(&_start);
+
+ memblock_enforce_memory_limit(memory_limit);
+
+ /*
+ * Make sure we align the reservation on PMD_SIZE since we will
+ * map the kernel in the linear mapping as read-only: we do not want
+ * any allocation to happen between _end and the next pmd aligned page.
+ */
+ if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
+ vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK;
+ /*
+ * Reserve from the start of the kernel to the end of the kernel
+ */
+ memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
+
+ phys_ram_end = memblock_end_of_DRAM();
+
+ /*
+ * Make sure we align the start of the memory on a PMD boundary so that
+ * at worst, we map the linear mapping with PMD mappings.
+ */
+ if (!IS_ENABLED(CONFIG_XIP_KERNEL))
+ phys_ram_base = memblock_start_of_DRAM() & PMD_MASK;
+
+ /*
+ * In 64-bit, any use of __va/__pa before this point is wrong as we
+ * did not know the start of DRAM before.
+ */
+ if (IS_ENABLED(CONFIG_64BIT))
+ kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base;
+
+ /*
+ * memblock allocator is not aware of the fact that last 4K bytes of
+ * the addressable memory can not be mapped because of IS_ERR_VALUE
+ * macro. Make sure that last 4k bytes are not usable by memblock
+ * if end of dram is equal to maximum addressable memory. For 64-bit
+ * kernel, this problem can't happen here as the end of the virtual
+ * address space is occupied by the kernel mapping then this check must
+ * be done as soon as the kernel mapping base address is determined.
+ */
+ if (!IS_ENABLED(CONFIG_64BIT)) {
+ max_mapped_addr = __pa(~(ulong)0);
+ if (max_mapped_addr == (phys_ram_end - 1))
+ memblock_set_current_limit(max_mapped_addr - 4096);
+ }
+
+ min_low_pfn = PFN_UP(phys_ram_base);
+ max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end);
+ high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
+
+ dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
+ set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
+
+ reserve_initrd_mem();
+
+ /*
+ * No allocation should be done before reserving the memory as defined
+ * in the device tree, otherwise the allocation could end up in a
+ * reserved region.
+ */
+ early_init_fdt_scan_reserved_mem();
+
+ /*
+ * If DTB is built in, no need to reserve its memblock.
+ * Otherwise, do reserve it but avoid using
+ * early_init_fdt_reserve_self() since __pa() does
+ * not work for DTB pointers that are fixmap addresses
+ */
+ if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
+ memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
+
+ dma_contiguous_reserve(dma32_phys_limit);
+ if (IS_ENABLED(CONFIG_64BIT))
+ hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
+}
+
+#ifdef CONFIG_MMU
+struct pt_alloc_ops pt_ops __initdata;
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
+
+pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
+
+#ifdef CONFIG_XIP_KERNEL
+#define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops))
+#define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
+#define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte))
+#define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir))
+#endif /* CONFIG_XIP_KERNEL */
+
+static const pgprot_t protection_map[16] = {
+ [VM_NONE] = PAGE_NONE,
+ [VM_READ] = PAGE_READ,
+ [VM_WRITE] = PAGE_COPY,
+ [VM_WRITE | VM_READ] = PAGE_COPY,
+ [VM_EXEC] = PAGE_EXEC,
+ [VM_EXEC | VM_READ] = PAGE_READ_EXEC,
+ [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC,
+ [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC,
+ [VM_SHARED] = PAGE_NONE,
+ [VM_SHARED | VM_READ] = PAGE_READ,
+ [VM_SHARED | VM_WRITE] = PAGE_SHARED,
+ [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
+ [VM_SHARED | VM_EXEC] = PAGE_EXEC,
+ [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READ_EXEC,
+ [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC,
+ [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC
+};
+DECLARE_VM_GET_PAGE_PROT
+
+void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
+{
+ unsigned long addr = __fix_to_virt(idx);
+ pte_t *ptep;
+
+ BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
+
+ ptep = &fixmap_pte[pte_index(addr)];
+
+ if (pgprot_val(prot))
+ set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
+ else
+ pte_clear(&init_mm, addr, ptep);
+ local_flush_tlb_page(addr);
+}
+
+static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
+{
+ return (pte_t *)((uintptr_t)pa);
+}
+
+static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
+{
+ clear_fixmap(FIX_PTE);
+ return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
+}
+
+static inline pte_t *__init get_pte_virt_late(phys_addr_t pa)
+{
+ return (pte_t *) __va(pa);
+}
+
+static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
+{
+ /*
+ * We only create PMD or PGD early mappings so we
+ * should never reach here with MMU disabled.
+ */
+ BUG();
+}
+
+static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
+{
+ return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
+}
+
+static phys_addr_t __init alloc_pte_late(uintptr_t va)
+{
+ struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
+
+ BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc));
+ return __pa((pte_t *)ptdesc_address(ptdesc));
+}
+
+static void __init create_pte_mapping(pte_t *ptep,
+ uintptr_t va, phys_addr_t pa,
+ phys_addr_t sz, pgprot_t prot)
+{
+ uintptr_t pte_idx = pte_index(va);
+
+ BUG_ON(sz != PAGE_SIZE);
+
+ if (pte_none(ptep[pte_idx]))
+ ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
+}
+
+#ifndef __PAGETABLE_PMD_FOLDED
+
+static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
+static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
+static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
+
+#ifdef CONFIG_XIP_KERNEL
+#define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd))
+#define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd))
+#define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd))
+#endif /* CONFIG_XIP_KERNEL */
+
+static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss;
+static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss;
+static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE);
+
+#ifdef CONFIG_XIP_KERNEL
+#define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d))
+#define fixmap_p4d ((p4d_t *)XIP_FIXUP(fixmap_p4d))
+#define early_p4d ((p4d_t *)XIP_FIXUP(early_p4d))
+#endif /* CONFIG_XIP_KERNEL */
+
+static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss;
+static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss;
+static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
+
+#ifdef CONFIG_XIP_KERNEL
+#define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud))
+#define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud))
+#define early_pud ((pud_t *)XIP_FIXUP(early_pud))
+#endif /* CONFIG_XIP_KERNEL */
+
+static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
+{
+ /* Before MMU is enabled */
+ return (pmd_t *)((uintptr_t)pa);
+}
+
+static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
+{
+ clear_fixmap(FIX_PMD);
+ return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
+}
+
+static pmd_t *__init get_pmd_virt_late(phys_addr_t pa)
+{
+ return (pmd_t *) __va(pa);
+}
+
+static phys_addr_t __init alloc_pmd_early(uintptr_t va)
+{
+ BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT);
+
+ return (uintptr_t)early_pmd;
+}
+
+static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
+{
+ return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
+}
+
+static phys_addr_t __init alloc_pmd_late(uintptr_t va)
+{
+ struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
+
+ BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc));
+ return __pa((pmd_t *)ptdesc_address(ptdesc));
+}
+
+static void __init create_pmd_mapping(pmd_t *pmdp,
+ uintptr_t va, phys_addr_t pa,
+ phys_addr_t sz, pgprot_t prot)
+{
+ pte_t *ptep;
+ phys_addr_t pte_phys;
+ uintptr_t pmd_idx = pmd_index(va);
+
+ if (sz == PMD_SIZE) {
+ if (pmd_none(pmdp[pmd_idx]))
+ pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
+ return;
+ }
+
+ if (pmd_none(pmdp[pmd_idx])) {
+ pte_phys = pt_ops.alloc_pte(va);
+ pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
+ ptep = pt_ops.get_pte_virt(pte_phys);
+ memset(ptep, 0, PAGE_SIZE);
+ } else {
+ pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
+ ptep = pt_ops.get_pte_virt(pte_phys);
+ }
+
+ create_pte_mapping(ptep, va, pa, sz, prot);
+}
+
+static pud_t *__init get_pud_virt_early(phys_addr_t pa)
+{
+ return (pud_t *)((uintptr_t)pa);
+}
+
+static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa)
+{
+ clear_fixmap(FIX_PUD);
+ return (pud_t *)set_fixmap_offset(FIX_PUD, pa);
+}
+
+static pud_t *__init get_pud_virt_late(phys_addr_t pa)
+{
+ return (pud_t *)__va(pa);
+}
+
+static phys_addr_t __init alloc_pud_early(uintptr_t va)
+{
+ /* Only one PUD is available for early mapping */
+ BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
+
+ return (uintptr_t)early_pud;
+}
+
+static phys_addr_t __init alloc_pud_fixmap(uintptr_t va)
+{
+ return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
+}
+
+static phys_addr_t alloc_pud_late(uintptr_t va)
+{
+ unsigned long vaddr;
+
+ vaddr = __get_free_page(GFP_KERNEL);
+ BUG_ON(!vaddr);
+ return __pa(vaddr);
+}
+
+static p4d_t *__init get_p4d_virt_early(phys_addr_t pa)
+{
+ return (p4d_t *)((uintptr_t)pa);
+}
+
+static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa)
+{
+ clear_fixmap(FIX_P4D);
+ return (p4d_t *)set_fixmap_offset(FIX_P4D, pa);
+}
+
+static p4d_t *__init get_p4d_virt_late(phys_addr_t pa)
+{
+ return (p4d_t *)__va(pa);
+}
+
+static phys_addr_t __init alloc_p4d_early(uintptr_t va)
+{
+ /* Only one P4D is available for early mapping */
+ BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
+
+ return (uintptr_t)early_p4d;
+}
+
+static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va)
+{
+ return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
+}
+
+static phys_addr_t alloc_p4d_late(uintptr_t va)
+{
+ unsigned long vaddr;
+
+ vaddr = __get_free_page(GFP_KERNEL);
+ BUG_ON(!vaddr);
+ return __pa(vaddr);
+}
+
+static void __init create_pud_mapping(pud_t *pudp,
+ uintptr_t va, phys_addr_t pa,
+ phys_addr_t sz, pgprot_t prot)
+{
+ pmd_t *nextp;
+ phys_addr_t next_phys;
+ uintptr_t pud_index = pud_index(va);
+
+ if (sz == PUD_SIZE) {
+ if (pud_val(pudp[pud_index]) == 0)
+ pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot);
+ return;
+ }
+
+ if (pud_val(pudp[pud_index]) == 0) {
+ next_phys = pt_ops.alloc_pmd(va);
+ pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE);
+ nextp = pt_ops.get_pmd_virt(next_phys);
+ memset(nextp, 0, PAGE_SIZE);
+ } else {
+ next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index]));
+ nextp = pt_ops.get_pmd_virt(next_phys);
+ }
+
+ create_pmd_mapping(nextp, va, pa, sz, prot);
+}
+
+static void __init create_p4d_mapping(p4d_t *p4dp,
+ uintptr_t va, phys_addr_t pa,
+ phys_addr_t sz, pgprot_t prot)
+{
+ pud_t *nextp;
+ phys_addr_t next_phys;
+ uintptr_t p4d_index = p4d_index(va);
+
+ if (sz == P4D_SIZE) {
+ if (p4d_val(p4dp[p4d_index]) == 0)
+ p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot);
+ return;
+ }
+
+ if (p4d_val(p4dp[p4d_index]) == 0) {
+ next_phys = pt_ops.alloc_pud(va);
+ p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE);
+ nextp = pt_ops.get_pud_virt(next_phys);
+ memset(nextp, 0, PAGE_SIZE);
+ } else {
+ next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index]));
+ nextp = pt_ops.get_pud_virt(next_phys);
+ }
+
+ create_pud_mapping(nextp, va, pa, sz, prot);
+}
+
+#define pgd_next_t p4d_t
+#define alloc_pgd_next(__va) (pgtable_l5_enabled ? \
+ pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ? \
+ pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)))
+#define get_pgd_next_virt(__pa) (pgtable_l5_enabled ? \
+ pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ? \
+ pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa)))
+#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
+ (pgtable_l5_enabled ? \
+ create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \
+ (pgtable_l4_enabled ? \
+ create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) : \
+ create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)))
+#define fixmap_pgd_next (pgtable_l5_enabled ? \
+ (uintptr_t)fixmap_p4d : (pgtable_l4_enabled ? \
+ (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd))
+#define trampoline_pgd_next (pgtable_l5_enabled ? \
+ (uintptr_t)trampoline_p4d : (pgtable_l4_enabled ? \
+ (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd))
+#else
+#define pgd_next_t pte_t
+#define alloc_pgd_next(__va) pt_ops.alloc_pte(__va)
+#define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
+#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
+ create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
+#define fixmap_pgd_next ((uintptr_t)fixmap_pte)
+#define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
+#define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
+#define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
+#endif /* __PAGETABLE_PMD_FOLDED */
+
+void __init create_pgd_mapping(pgd_t *pgdp,
+ uintptr_t va, phys_addr_t pa,
+ phys_addr_t sz, pgprot_t prot)
+{
+ pgd_next_t *nextp;
+ phys_addr_t next_phys;
+ uintptr_t pgd_idx = pgd_index(va);
+
+ if (sz == PGDIR_SIZE) {
+ if (pgd_val(pgdp[pgd_idx]) == 0)
+ pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
+ return;
+ }
+
+ if (pgd_val(pgdp[pgd_idx]) == 0) {
+ next_phys = alloc_pgd_next(va);
+ pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
+ nextp = get_pgd_next_virt(next_phys);
+ memset(nextp, 0, PAGE_SIZE);
+ } else {
+ next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
+ nextp = get_pgd_next_virt(next_phys);
+ }
+
+ create_pgd_next_mapping(nextp, va, pa, sz, prot);
+}
+
+static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
+ phys_addr_t size)
+{
+ if (!(pa & (PGDIR_SIZE - 1)) && !(va & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE)
+ return PGDIR_SIZE;
+
+ if (!(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
+ return P4D_SIZE;
+
+ if (!(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
+ return PUD_SIZE;
+
+ if (!(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
+ return PMD_SIZE;
+
+ return PAGE_SIZE;
+}
+
+#ifdef CONFIG_XIP_KERNEL
+#define phys_ram_base (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base))
+extern char _xiprom[], _exiprom[], __data_loc;
+
+/* called from head.S with MMU off */
+asmlinkage void __init __copy_data(void)
+{
+ void *from = (void *)(&__data_loc);
+ void *to = (void *)CONFIG_PHYS_RAM_BASE;
+ size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata));
+
+ memcpy(to, from, sz);
+}
+#endif
+
+#ifdef CONFIG_STRICT_KERNEL_RWX
+static __init pgprot_t pgprot_from_va(uintptr_t va)
+{
+ if (is_va_kernel_text(va))
+ return PAGE_KERNEL_READ_EXEC;
+
+ /*
+ * In 64-bit kernel, the kernel mapping is outside the linear mapping so
+ * we must protect its linear mapping alias from being executed and
+ * written.
+ * And rodata section is marked readonly in mark_rodata_ro.
+ */
+ if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va))
+ return PAGE_KERNEL_READ;
+
+ return PAGE_KERNEL;
+}
+
+void mark_rodata_ro(void)
+{
+ set_kernel_memory(__start_rodata, _data, set_memory_ro);
+ if (IS_ENABLED(CONFIG_64BIT))
+ set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data),
+ set_memory_ro);
+
+ debug_checkwx();
+}
+#else
+static __init pgprot_t pgprot_from_va(uintptr_t va)
+{
+ if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va))
+ return PAGE_KERNEL;
+
+ return PAGE_KERNEL_EXEC;
+}
+#endif /* CONFIG_STRICT_KERNEL_RWX */
+
+#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
+u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa);
+
+static void __init disable_pgtable_l5(void)
+{
+ pgtable_l5_enabled = false;
+ kernel_map.page_offset = PAGE_OFFSET_L4;
+ satp_mode = SATP_MODE_48;
+}
+
+static void __init disable_pgtable_l4(void)
+{
+ pgtable_l4_enabled = false;
+ kernel_map.page_offset = PAGE_OFFSET_L3;
+ satp_mode = SATP_MODE_39;
+}
+
+static int __init print_no4lvl(char *p)
+{
+ pr_info("Disabled 4-level and 5-level paging");
+ return 0;
+}
+early_param("no4lvl", print_no4lvl);
+
+static int __init print_no5lvl(char *p)
+{
+ pr_info("Disabled 5-level paging");
+ return 0;
+}
+early_param("no5lvl", print_no5lvl);
+
+/*
+ * There is a simple way to determine if 4-level is supported by the
+ * underlying hardware: establish 1:1 mapping in 4-level page table mode
+ * then read SATP to see if the configuration was taken into account
+ * meaning sv48 is supported.
+ */
+static __init void set_satp_mode(uintptr_t dtb_pa)
+{
+ u64 identity_satp, hw_satp;
+ uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
+ u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa);
+
+ if (satp_mode_cmdline == SATP_MODE_57) {
+ disable_pgtable_l5();
+ } else if (satp_mode_cmdline == SATP_MODE_48) {
+ disable_pgtable_l5();
+ disable_pgtable_l4();
+ return;
+ }
+
+ create_p4d_mapping(early_p4d,
+ set_satp_mode_pmd, (uintptr_t)early_pud,
+ P4D_SIZE, PAGE_TABLE);
+ create_pud_mapping(early_pud,
+ set_satp_mode_pmd, (uintptr_t)early_pmd,
+ PUD_SIZE, PAGE_TABLE);
+ /* Handle the case where set_satp_mode straddles 2 PMDs */
+ create_pmd_mapping(early_pmd,
+ set_satp_mode_pmd, set_satp_mode_pmd,
+ PMD_SIZE, PAGE_KERNEL_EXEC);
+ create_pmd_mapping(early_pmd,
+ set_satp_mode_pmd + PMD_SIZE,
+ set_satp_mode_pmd + PMD_SIZE,
+ PMD_SIZE, PAGE_KERNEL_EXEC);
+retry:
+ create_pgd_mapping(early_pg_dir,
+ set_satp_mode_pmd,
+ pgtable_l5_enabled ?
+ (uintptr_t)early_p4d : (uintptr_t)early_pud,
+ PGDIR_SIZE, PAGE_TABLE);
+
+ identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode;
+
+ local_flush_tlb_all();
+ csr_write(CSR_SATP, identity_satp);
+ hw_satp = csr_swap(CSR_SATP, 0ULL);
+ local_flush_tlb_all();
+
+ if (hw_satp != identity_satp) {
+ if (pgtable_l5_enabled) {
+ disable_pgtable_l5();
+ memset(early_pg_dir, 0, PAGE_SIZE);
+ goto retry;
+ }
+ disable_pgtable_l4();
+ }
+
+ memset(early_pg_dir, 0, PAGE_SIZE);
+ memset(early_p4d, 0, PAGE_SIZE);
+ memset(early_pud, 0, PAGE_SIZE);
+ memset(early_pmd, 0, PAGE_SIZE);
+}
+#endif
+
+/*
+ * setup_vm() is called from head.S with MMU-off.
+ *
+ * Following requirements should be honoured for setup_vm() to work
+ * correctly:
+ * 1) It should use PC-relative addressing for accessing kernel symbols.
+ * To achieve this we always use GCC cmodel=medany.
+ * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
+ * so disable compiler instrumentation when FTRACE is enabled.
+ *
+ * Currently, the above requirements are honoured by using custom CFLAGS
+ * for init.o in mm/Makefile.
+ */
+
+#ifndef __riscv_cmodel_medany
+#error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
+#endif
+
+#ifdef CONFIG_RELOCATABLE
+extern unsigned long __rela_dyn_start, __rela_dyn_end;
+
+static void __init relocate_kernel(void)
+{
+ Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start;
+ /*
+ * This holds the offset between the linked virtual address and the
+ * relocated virtual address.
+ */
+ uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR;
+ /*
+ * This holds the offset between kernel linked virtual address and
+ * physical address.
+ */
+ uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr;
+
+ for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) {
+ Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset);
+ Elf64_Addr relocated_addr = rela->r_addend;
+
+ if (rela->r_info != R_RISCV_RELATIVE)
+ continue;
+
+ /*
+ * Make sure to not relocate vdso symbols like rt_sigreturn
+ * which are linked from the address 0 in vmlinux since
+ * vdso symbol addresses are actually used as an offset from
+ * mm->context.vdso in VDSO_OFFSET macro.
+ */
+ if (relocated_addr >= KERNEL_LINK_ADDR)
+ relocated_addr += reloc_offset;
+
+ *(Elf64_Addr *)addr = relocated_addr;
+ }
+}
+#endif /* CONFIG_RELOCATABLE */
+
+#ifdef CONFIG_XIP_KERNEL
+static void __init create_kernel_page_table(pgd_t *pgdir,
+ __always_unused bool early)
+{
+ uintptr_t va, end_va;
+
+ /* Map the flash resident part */
+ end_va = kernel_map.virt_addr + kernel_map.xiprom_sz;
+ for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
+ create_pgd_mapping(pgdir, va,
+ kernel_map.xiprom + (va - kernel_map.virt_addr),
+ PMD_SIZE, PAGE_KERNEL_EXEC);
+
+ /* Map the data in RAM */
+ end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size;
+ for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE)
+ create_pgd_mapping(pgdir, va,
+ kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)),
+ PMD_SIZE, PAGE_KERNEL);
+}
+#else
+static void __init create_kernel_page_table(pgd_t *pgdir, bool early)
+{
+ uintptr_t va, end_va;
+
+ end_va = kernel_map.virt_addr + kernel_map.size;
+ for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
+ create_pgd_mapping(pgdir, va,
+ kernel_map.phys_addr + (va - kernel_map.virt_addr),
+ PMD_SIZE,
+ early ?
+ PAGE_KERNEL_EXEC : pgprot_from_va(va));
+}
+#endif
+
+/*
+ * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel,
+ * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR
+ * entry.
+ */
+static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va,
+ uintptr_t dtb_pa)
+{
+#ifndef CONFIG_BUILTIN_DTB
+ uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
+
+ /* Make sure the fdt fixmap address is always aligned on PMD size */
+ BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE));
+
+ /* In 32-bit only, the fdt lies in its own PGD */
+ if (!IS_ENABLED(CONFIG_64BIT)) {
+ create_pgd_mapping(early_pg_dir, fix_fdt_va,
+ pa, MAX_FDT_SIZE, PAGE_KERNEL);
+ } else {
+ create_pmd_mapping(fixmap_pmd, fix_fdt_va,
+ pa, PMD_SIZE, PAGE_KERNEL);
+ create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE,
+ pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
+ }
+
+ dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1));
+#else
+ /*
+ * For 64-bit kernel, __va can't be used since it would return a linear
+ * mapping address whereas dtb_early_va will be used before
+ * setup_vm_final installs the linear mapping. For 32-bit kernel, as the
+ * kernel is mapped in the linear mapping, that makes no difference.
+ */
+ dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
+#endif
+
+ dtb_early_pa = dtb_pa;
+}
+
+/*
+ * MMU is not enabled, the page tables are allocated directly using
+ * early_pmd/pud/p4d and the address returned is the physical one.
+ */
+static void __init pt_ops_set_early(void)
+{
+ pt_ops.alloc_pte = alloc_pte_early;
+ pt_ops.get_pte_virt = get_pte_virt_early;
+#ifndef __PAGETABLE_PMD_FOLDED
+ pt_ops.alloc_pmd = alloc_pmd_early;
+ pt_ops.get_pmd_virt = get_pmd_virt_early;
+ pt_ops.alloc_pud = alloc_pud_early;
+ pt_ops.get_pud_virt = get_pud_virt_early;
+ pt_ops.alloc_p4d = alloc_p4d_early;
+ pt_ops.get_p4d_virt = get_p4d_virt_early;
+#endif
+}
+
+/*
+ * MMU is enabled but page table setup is not complete yet.
+ * fixmap page table alloc functions must be used as a means to temporarily
+ * map the allocated physical pages since the linear mapping does not exist yet.
+ *
+ * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va,
+ * but it will be used as described above.
+ */
+static void __init pt_ops_set_fixmap(void)
+{
+ pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap);
+ pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap);
+#ifndef __PAGETABLE_PMD_FOLDED
+ pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap);
+ pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap);
+ pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap);
+ pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap);
+ pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap);
+ pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap);
+#endif
+}
+
+/*
+ * MMU is enabled and page table setup is complete, so from now, we can use
+ * generic page allocation functions to setup page table.
+ */
+static void __init pt_ops_set_late(void)
+{
+ pt_ops.alloc_pte = alloc_pte_late;
+ pt_ops.get_pte_virt = get_pte_virt_late;
+#ifndef __PAGETABLE_PMD_FOLDED
+ pt_ops.alloc_pmd = alloc_pmd_late;
+ pt_ops.get_pmd_virt = get_pmd_virt_late;
+ pt_ops.alloc_pud = alloc_pud_late;
+ pt_ops.get_pud_virt = get_pud_virt_late;
+ pt_ops.alloc_p4d = alloc_p4d_late;
+ pt_ops.get_p4d_virt = get_p4d_virt_late;
+#endif
+}
+
+#ifdef CONFIG_RANDOMIZE_BASE
+extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa);
+extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa);
+
+static int __init print_nokaslr(char *p)
+{
+ pr_info("Disabled KASLR");
+ return 0;
+}
+early_param("nokaslr", print_nokaslr);
+
+unsigned long kaslr_offset(void)
+{
+ return kernel_map.virt_offset;
+}
+#endif
+
+asmlinkage void __init setup_vm(uintptr_t dtb_pa)
+{
+ pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd;
+
+#ifdef CONFIG_RANDOMIZE_BASE
+ if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) {
+ u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa);
+ u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start);
+ u32 nr_pos;
+
+ /*
+ * Compute the number of positions available: we are limited
+ * by the early page table that only has one PUD and we must
+ * be aligned on PMD_SIZE.
+ */
+ nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE;
+
+ kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE;
+ }
+#endif
+
+ kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset;
+ kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
+
+#ifdef CONFIG_XIP_KERNEL
+ kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
+ kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
+
+ phys_ram_base = CONFIG_PHYS_RAM_BASE;
+ kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE;
+ kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata);
+
+ kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom;
+#else
+ kernel_map.phys_addr = (uintptr_t)(&_start);
+ kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
+#endif
+
+#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
+ set_satp_mode(dtb_pa);
+#endif
+
+ /*
+ * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem,
+ * where we have the system memory layout: this allows us to align
+ * the physical and virtual mappings and then make use of PUD/P4D/PGD
+ * for the linear mapping. This is only possible because the kernel
+ * mapping lies outside the linear mapping.
+ * In 32-bit however, as the kernel resides in the linear mapping,
+ * setup_vm_final can not change the mapping established here,
+ * otherwise the same kernel addresses would get mapped to different
+ * physical addresses (if the start of dram is different from the
+ * kernel physical address start).
+ */
+ kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ?
+ 0UL : PAGE_OFFSET - kernel_map.phys_addr;
+ kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
+
+ /*
+ * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit
+ * kernel, whereas for 64-bit kernel, the end of the virtual address
+ * space is occupied by the modules/BPF/kernel mappings which reduces
+ * the available size of the linear mapping.
+ */
+ memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0);
+
+ /* Sanity check alignment and size */
+ BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
+ BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0);
+
+#ifdef CONFIG_64BIT
+ /*
+ * The last 4K bytes of the addressable memory can not be mapped because
+ * of IS_ERR_VALUE macro.
+ */
+ BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K);
+#endif
+
+#ifdef CONFIG_RELOCATABLE
+ /*
+ * Early page table uses only one PUD, which makes it possible
+ * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset
+ * makes the kernel cross over a PUD_SIZE boundary, raise a bug
+ * since a part of the kernel would not get mapped.
+ */
+ BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size);
+ relocate_kernel();
+#endif
+
+ apply_early_boot_alternatives();
+ pt_ops_set_early();
+
+ /* Setup early PGD for fixmap */
+ create_pgd_mapping(early_pg_dir, FIXADDR_START,
+ fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
+
+#ifndef __PAGETABLE_PMD_FOLDED
+ /* Setup fixmap P4D and PUD */
+ if (pgtable_l5_enabled)
+ create_p4d_mapping(fixmap_p4d, FIXADDR_START,
+ (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE);
+ /* Setup fixmap PUD and PMD */
+ if (pgtable_l4_enabled)
+ create_pud_mapping(fixmap_pud, FIXADDR_START,
+ (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
+ create_pmd_mapping(fixmap_pmd, FIXADDR_START,
+ (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
+ /* Setup trampoline PGD and PMD */
+ create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
+ trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
+ if (pgtable_l5_enabled)
+ create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr,
+ (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE);
+ if (pgtable_l4_enabled)
+ create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
+ (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
+#ifdef CONFIG_XIP_KERNEL
+ create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
+ kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
+#else
+ create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
+ kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC);
+#endif
+#else
+ /* Setup trampoline PGD */
+ create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
+ kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC);
+#endif
+
+ /*
+ * Setup early PGD covering entire kernel which will allow
+ * us to reach paging_init(). We map all memory banks later
+ * in setup_vm_final() below.
+ */
+ create_kernel_page_table(early_pg_dir, true);
+
+ /* Setup early mapping for FDT early scan */
+ create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa);
+
+ /*
+ * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
+ * range can not span multiple pmds.
+ */
+ BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
+ != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
+
+#ifndef __PAGETABLE_PMD_FOLDED
+ /*
+ * Early ioremap fixmap is already created as it lies within first 2MB
+ * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
+ * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
+ * the user if not.
+ */
+ fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
+ fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
+ if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
+ WARN_ON(1);
+ pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
+ pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
+ pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
+ fix_to_virt(FIX_BTMAP_BEGIN));
+ pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
+ fix_to_virt(FIX_BTMAP_END));
+
+ pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
+ pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
+ }
+#endif
+
+ pt_ops_set_fixmap();
+}
+
+static void __init create_linear_mapping_range(phys_addr_t start,
+ phys_addr_t end,
+ uintptr_t fixed_map_size)
+{
+ phys_addr_t pa;
+ uintptr_t va, map_size;
+
+ for (pa = start; pa < end; pa += map_size) {
+ va = (uintptr_t)__va(pa);
+ map_size = fixed_map_size ? fixed_map_size :
+ best_map_size(pa, va, end - pa);
+
+ create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
+ pgprot_from_va(va));
+ }
+}
+
+static void __init create_linear_mapping_page_table(void)
+{
+ phys_addr_t start, end;
+ phys_addr_t kfence_pool __maybe_unused;
+ u64 i;
+
+#ifdef CONFIG_STRICT_KERNEL_RWX
+ phys_addr_t ktext_start = __pa_symbol(_start);
+ phys_addr_t ktext_size = __init_data_begin - _start;
+ phys_addr_t krodata_start = __pa_symbol(__start_rodata);
+ phys_addr_t krodata_size = _data - __start_rodata;
+
+ /* Isolate kernel text and rodata so they don't get mapped with a PUD */
+ memblock_mark_nomap(ktext_start, ktext_size);
+ memblock_mark_nomap(krodata_start, krodata_size);
+#endif
+
+#ifdef CONFIG_KFENCE
+ /*
+ * kfence pool must be backed by PAGE_SIZE mappings, so allocate it
+ * before we setup the linear mapping so that we avoid using hugepages
+ * for this region.
+ */
+ kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE);
+ BUG_ON(!kfence_pool);
+
+ memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE);
+ __kfence_pool = __va(kfence_pool);
+#endif
+
+ /* Map all memory banks in the linear mapping */
+ for_each_mem_range(i, &start, &end) {
+ if (start >= end)
+ break;
+ if (start <= __pa(PAGE_OFFSET) &&
+ __pa(PAGE_OFFSET) < end)
+ start = __pa(PAGE_OFFSET);
+ if (end >= __pa(PAGE_OFFSET) + memory_limit)
+ end = __pa(PAGE_OFFSET) + memory_limit;
+
+ create_linear_mapping_range(start, end, 0);
+ }
+
+#ifdef CONFIG_STRICT_KERNEL_RWX
+ create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0);
+ create_linear_mapping_range(krodata_start,
+ krodata_start + krodata_size, 0);
+
+ memblock_clear_nomap(ktext_start, ktext_size);
+ memblock_clear_nomap(krodata_start, krodata_size);
+#endif
+
+#ifdef CONFIG_KFENCE
+ create_linear_mapping_range(kfence_pool,
+ kfence_pool + KFENCE_POOL_SIZE,
+ PAGE_SIZE);
+
+ memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE);
+#endif
+}
+
+static void __init setup_vm_final(void)
+{
+ /* Setup swapper PGD for fixmap */
+#if !defined(CONFIG_64BIT)
+ /*
+ * In 32-bit, the device tree lies in a pgd entry, so it must be copied
+ * directly in swapper_pg_dir in addition to the pgd entry that points
+ * to fixmap_pte.
+ */
+ unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
+
+ set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
+#endif
+ create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
+ __pa_symbol(fixmap_pgd_next),
+ PGDIR_SIZE, PAGE_TABLE);
+
+ /* Map the linear mapping */
+ create_linear_mapping_page_table();
+
+ /* Map the kernel */
+ if (IS_ENABLED(CONFIG_64BIT))
+ create_kernel_page_table(swapper_pg_dir, false);
+
+#ifdef CONFIG_KASAN
+ kasan_swapper_init();
+#endif
+
+ /* Clear fixmap PTE and PMD mappings */
+ clear_fixmap(FIX_PTE);
+ clear_fixmap(FIX_PMD);
+ clear_fixmap(FIX_PUD);
+ clear_fixmap(FIX_P4D);
+
+ /* Move to swapper page table */
+ csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode);
+ local_flush_tlb_all();
+
+ pt_ops_set_late();
+}
+#else
+asmlinkage void __init setup_vm(uintptr_t dtb_pa)
+{
+ dtb_early_va = (void *)dtb_pa;
+ dtb_early_pa = dtb_pa;
+}
+
+static inline void setup_vm_final(void)
+{
+}
+#endif /* CONFIG_MMU */
+
+/* Reserve 128M low memory by default for swiotlb buffer */
+#define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20)
+
+static int __init reserve_crashkernel_low(unsigned long long low_size)
+{
+ unsigned long long low_base;
+
+ low_base = memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_limit);
+ if (!low_base) {
+ pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size);
+ return -ENOMEM;
+ }
+
+ pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
+ low_base, low_base + low_size, low_size >> 20);
+
+ crashk_low_res.start = low_base;
+ crashk_low_res.end = low_base + low_size - 1;
+
+ return 0;
+}
+
+/*
+ * reserve_crashkernel() - reserves memory for crash kernel
+ *
+ * This function reserves memory area given in "crashkernel=" kernel command
+ * line parameter. The memory reserved is used by dump capture kernel when
+ * primary kernel is crashing.
+ */
+static void __init reserve_crashkernel(void)
+{
+ unsigned long long crash_base = 0;
+ unsigned long long crash_size = 0;
+ unsigned long long crash_low_size = 0;
+ unsigned long search_start = memblock_start_of_DRAM();
+ unsigned long search_end = (unsigned long)dma32_phys_limit;
+ char *cmdline = boot_command_line;
+ bool fixed_base = false;
+ bool high = false;
+
+ int ret = 0;
+
+ if (!IS_ENABLED(CONFIG_KEXEC_CORE))
+ return;
+ /*
+ * Don't reserve a region for a crash kernel on a crash kernel
+ * since it doesn't make much sense and we have limited memory
+ * resources.
+ */
+ if (is_kdump_kernel()) {
+ pr_info("crashkernel: ignoring reservation request\n");
+ return;
+ }
+
+ ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
+ &crash_size, &crash_base);
+ if (ret == -ENOENT) {
+ /* Fallback to crashkernel=X,[high,low] */
+ ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base);
+ if (ret || !crash_size)
+ return;
+
+ /*
+ * crashkernel=Y,low is valid only when crashkernel=X,high
+ * is passed.
+ */
+ ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base);
+ if (ret == -ENOENT)
+ crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+ else if (ret)
+ return;
+
+ search_start = (unsigned long)dma32_phys_limit;
+ search_end = memblock_end_of_DRAM();
+ high = true;
+ } else if (ret || !crash_size) {
+ /* Invalid argument value specified */
+ return;
+ }
+
+ crash_size = PAGE_ALIGN(crash_size);
+
+ if (crash_base) {
+ fixed_base = true;
+ search_start = crash_base;
+ search_end = crash_base + crash_size;
+ }
+
+ /*
+ * Current riscv boot protocol requires 2MB alignment for
+ * RV64 and 4MB alignment for RV32 (hugepage size)
+ *
+ * Try to alloc from 32bit addressible physical memory so that
+ * swiotlb can work on the crash kernel.
+ */
+ crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
+ search_start, search_end);
+ if (crash_base == 0) {
+ /*
+ * For crashkernel=size[KMG]@offset[KMG], print out failure
+ * message if can't reserve the specified region.
+ */
+ if (fixed_base) {
+ pr_warn("crashkernel: allocating failed with given size@offset\n");
+ return;
+ }
+
+ if (high) {
+ /*
+ * For crashkernel=size[KMG],high, if the first attempt was
+ * for high memory, fall back to low memory.
+ */
+ search_start = memblock_start_of_DRAM();
+ search_end = (unsigned long)dma32_phys_limit;
+ } else {
+ /*
+ * For crashkernel=size[KMG], if the first attempt was for
+ * low memory, fall back to high memory, the minimum required
+ * low memory will be reserved later.
+ */
+ search_start = (unsigned long)dma32_phys_limit;
+ search_end = memblock_end_of_DRAM();
+ crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
+ }
+
+ crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
+ search_start, search_end);
+ if (crash_base == 0) {
+ pr_warn("crashkernel: couldn't allocate %lldKB\n",
+ crash_size >> 10);
+ return;
+ }
+ }
+
+ if ((crash_base >= dma32_phys_limit) && crash_low_size &&
+ reserve_crashkernel_low(crash_low_size)) {
+ memblock_phys_free(crash_base, crash_size);
+ return;
+ }
+
+ pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",
+ crash_base, crash_base + crash_size, crash_size >> 20);
+
+ crashk_res.start = crash_base;
+ crashk_res.end = crash_base + crash_size - 1;
+}
+
+void __init paging_init(void)
+{
+ setup_bootmem();
+ setup_vm_final();
+
+ /* Depend on that Linear Mapping is ready */
+ memblock_allow_resize();
+}
+
+void __init misc_mem_init(void)
+{
+ early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
+ arch_numa_init();
+ sparse_init();
+ zone_sizes_init();
+ reserve_crashkernel();
+ memblock_dump_all();
+}
+
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+ struct vmem_altmap *altmap)
+{
+ return vmemmap_populate_basepages(start, end, node, NULL);
+}
+#endif
+
+#if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
+/*
+ * Pre-allocates page-table pages for a specific area in the kernel
+ * page-table. Only the level which needs to be synchronized between
+ * all page-tables is allocated because the synchronization can be
+ * expensive.
+ */
+static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end,
+ const char *area)
+{
+ unsigned long addr;
+ const char *lvl;
+
+ for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
+ pgd_t *pgd = pgd_offset_k(addr);
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ lvl = "p4d";
+ p4d = p4d_alloc(&init_mm, pgd, addr);
+ if (!p4d)
+ goto failed;
+
+ if (pgtable_l5_enabled)
+ continue;
+
+ lvl = "pud";
+ pud = pud_alloc(&init_mm, p4d, addr);
+ if (!pud)
+ goto failed;
+
+ if (pgtable_l4_enabled)
+ continue;
+
+ lvl = "pmd";
+ pmd = pmd_alloc(&init_mm, pud, addr);
+ if (!pmd)
+ goto failed;
+ }
+ return;
+
+failed:
+ /*
+ * The pages have to be there now or they will be missing in
+ * process page-tables later.
+ */
+ panic("Failed to pre-allocate %s pages for %s area\n", lvl, area);
+}
+
+void __init pgtable_cache_init(void)
+{
+ preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc");
+ if (IS_ENABLED(CONFIG_MODULES))
+ preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules");
+}
+#endif